1. Log into your SiteWorx account. (eg: www.example.com:2443/siteworx/ )
2. Under "SiteWorx Menu", click the "Hosting Features" menu item if it is not already open.
3. Click the "Domain" menu item and then click on "Secondary" option.
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4. Under "Existing Domains " tab, Select Appropriate domain name you want to delete.
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5. Click the "Delete" button.
6. A conformation window will appear, Again click on "Delete" button.
You should see a success message notifying you that your Secondary domain has been removed.